Smarty UDC Initial Impressions

As it has been stated when you adjust (raise) the duration the ECM still thinks it's pumping the same amount of fuel, but your pumping a lot more. It still takes the same power to go the speed your cruising, so the ECM goes lower in the load cells for duration and thinks your pumping x fuel, but your really pumping 2x.

The labels for duration are not correct. The duration table has nothing to do with rpms, that's just how MADS labeled it. So 2000 rpms and below is the bottom end of cruise and lower.

IMHO, if you want to increase duration for additional power then only do so in the last 3 or 4 rows. I only do the last 3. This will keep your low end smoke the same, and still be smooth at low throttle but give you the power you want at 75% throttle and above. So if you want 20% more fuel I would add 20% to the 3600 rpm column, 15% to the 3400, 10% to the 3300 and 5% to the 3200 column. That will give you a smooth increase in fuel to the gain you want. You only need to increase the top end fueling, not the entire table, to get more power when WOT.

I know I have posted this in other threads, and maybe this one, but here it is again. It's the correct labels for the duration table, and makes it much easier to understand and modify.

Duration-1.jpg
 
How can I tune for faster warm times on an 03.

150 hp sticks, 62/71/14 and s480/87/1.10ar, auto trans. winter front on grill and right behind the bumper top to bottom.

I drive 15 minutes to school with a 5-10 minute idle time.
- I raised the idle timing from 3.0* to 4.0* in the idle load range.
- Should I raise it more to say 6.0* to put more heat on the pistons?

-Cruising range is 4.2* to 4.7* EGTs are what I consider normal 600*-800*.


I only want input on using tuning to speed up the time to normal operating temps.
 
I have thought about this a bit and I am not sure you can do much for it. Think about it, a cold motor is not efficient, and thus has horrible emissions, if something could be done then I think they would have. But I think advancing the timing would put more heat to the pistons and less heat into the head, you want heat in the head for coolant warming. Maybe try reducing the timing to raise idle EGT's.

The 04.5-07's run much less timing, the 650 column is -4.0° and the 800 is between 2.5° and 0.9°. Thou I don't know how much the pilot differs between the two.

Your 5-10 minute idle time is really a waste of fuel, plug it in and idle it no more than 3-5 minutes and drive.
 
AH64ID said:
I have thought about this a bit and I am not sure you can do much for it. Think about it, a cold motor is not efficient, and thus has horrible emissions, if something could be done then I think they would have. But I think advancing the timing would put more heat to the pistons and less heat into the head, you want heat in the head for coolant warming. Maybe try reducing the timing to raise idle EGT's.

The 04.5-07's run much less timing, the 650 column is -4.0° and the 800 is between 2.5° and 0.9°. Thou I don't know how much the pilot differs between the two.

Your 5-10 minute idle time is really a waste of fuel, plug it in and idle it no more than 3-5 minutes and drive.
Click to expand...

Lower timing hmm... Ill try that. Thanks.

Not concerned about fuel economy in town I get 12-15 mpg.
 
Give it a shot, but like I said, I don't think it will be appreciable.

There is also cylinder washing to consider, the 3-5 minutes is a Cummins thing not mine.
 
Smarty UDC Improvement Suggestions

It Would be nice for future feature to include:
Select Multiple cells and type in the value you want for all of them.

Some Better Auto Smoothing feature.

Some quick views in 3D table So you are Normal to whatever face you want to see. Right view, Front view, Left, Etc

Copy and Paste from spread sheet or other UDC file

Some generic Timing table even if its one cell at a time. So You can enter a timing vale and it would give you an estimated value for duration and rail pressure. With a few parameter's to account for injector size...

UDC is Great just looking for improvements.

Is there anyway to add some adjustment with controlling FCA?
 
AH64ID said:
As it has been stated when you adjust (raise) the duration the ECM still thinks it's pumping the same amount of fuel, but your pumping a lot more. It still takes the same power to go the speed your cruising, so the ECM goes lower in the load cells for duration and thinks your pumping x fuel, but your really pumping 2x.

The labels for duration are not correct. The duration table has nothing to do with rpms, that's just how MADS labeled it. So 2000 rpms and below is the bottom end of cruise and lower.

IMHO, if you want to increase duration for additional power then only do so in the last 3 or 4 rows. I only do the last 3. This will keep your low end smoke the same, and still be smooth at low throttle but give you the power you want at 75% throttle and above. So if you want 20% more fuel I would add 20% to the 3600 rpm column, 15% to the 3400, 10% to the 3300 and 5% to the 3200 column. That will give you a smooth increase in fuel to the gain you want. You only need to increase the top end fueling, not the entire table, to get more power when WOT.

I know I have posted this in other threads, and maybe this one, but here it is again. It's the correct labels for the duration table, and makes it much easier to understand and modify.

Duration-1.jpg
Click to expand...

Thanks AH!
 
I finally took the time to sit down and play with my timing calculator. It was fairly automatic before, but I had to manually select the cell with the proper calculated duration to get the true pulse width. Now it's fully automatic.

The inputs are duration, pressure, and desired calculation (% BTDC). That's it.. it will then output the timing.

I am going to clean it up a bit, and then I will consider sharing it with a couple of folks for evaluation. Until it's vetted I don't want to send it to too many people, as a simple formula mistake could be costly.

I was rather impressed with myself thou. When pulling all the pulse width data by hand I only got 1 cell off on one calculation and that only accounted for 19us of error. Pretty good, considering there are 285 cells to populate.
 
AH64ID said:
I finally took the time to sit down and play with my timing calculator. It was fairly automatic before, but I had to manually select the cell with the proper calculated duration to get the true pulse width. Now it's fully automatic.

The inputs are duration, pressure, and desired calculation (% BTDC). That's it.. it will then output the timing.

I am going to clean it up a bit, and then I will consider sharing it with a couple of folks for evaluation. Until it's vetted I don't want to send it to too many people, as a simple formula mistake could be costly.

I was rather impressed with myself thou. When pulling all the pulse width data by hand I only got 1 cell off on one calculation and that only accounted for 19us of error. Pretty good, considering there are 285 cells to populate.
Click to expand...

You are the man John, I don't know how many trees I've killed using scratch paper to calculate everything by hand to this point haha. :rockwoot:
 
Your always on top of it John, interested in seeing how you did the formulas when you have it nailed down..

2005 - HE351/A5K - ARP - Arson lll - 70HP Nozzles
 
Great John! I'll volunteer myself. Now I have a timing question for you. How does injector tip angle effect timing? Besides the number of fuel shots being different between the 03's and the 05's is the spray angle effecting the timing maps that much? So would a larger spray angle reduce the amount of timing?
 
So in talking about duration and timing I thought I would add this.

The duration table tells the ECM how long it takes to inject "x" fuel at "y" pressure, so it's more of a calibration table. It does not give the exact pulse width for a given load/rpm, that has to be calculated (extrapolated, blended) by the ECM for every injection.

What I have attached is an example of a calculated pulse width table based on stock duration and pressure. To calculate this the ECM (or a timing calculator) will take the desired fuel rate (load) and rpm to the rail pressure table. So lets use 100% load and 2000 rpms. On the stock table that commands 20,885 psi (which is 144 MPa; I use MPa because I only had to extrapolate 156 pressure columns, vs 145x that many). Now if you look at the modified labeling on the duration table you won't find a row that has 20,885psi as a whole number, so we have to extrapolate (just like the ECM will). That extrapolated value comes out to a desired pulse width of 2126us (so it takes 2126us of injector open time to flow 140mm3(100% load) at 144 MPa (20,885 psi)).

If you compare that to the UDC labeling you can see there is a big difference. According to the UDC labeling 2000 rpms and 100% load would be 386us, and that's not correct. This is why it's necessary to look at the modified labels I posted if your going to calculate pulse width and/or timing.

So, like I mentioned, the photo is what the desired pulse width will be with stock pressure and duration in relation to rpms and load. This table must be calculated, it's not available anywhere in the ECM that I am aware of, certainly not anything we can see with UDC. The ECM will then blend/calculate between the cells when the load and/or rpms are not exactly as indicated. (i.e. 2050 rpms).

There was also a question as to why duration increases with rpms. You can see from the attached photo that it doesn't. The reason it doesn't (generally) is because the higher the pressure the faster the fuel is injected (this is why pressure boxes make more power, they get more fuel in the cylinder per injection event and the additional fuel is what makes the power, not necessarily the pressure). As an example a 2000us pulse width gets you about 110mm3 of fuel at 14.5K psi, and 140mm4 at 23.2K psi.

So under WOT acceleration the pulse width will decrease as rpms increase, until you hit your peak pressure and then the pulse with stay the same regardless of rpms. With a constant rpm and increasing load (pulling a hill with a trailer) the pulse width will increase almost all the way to WOT, but the depends on how your pressure map is built. Looking at the stock pulse width table you can see that at some rpms it increases all the way to WOT, but at some it dips and then climbs back up.

So, lastly, when we modify the duration table we are not directly modifying the pulse width. Instead what we are doing is changing the "calibration" numbers and telling the ECM it take more (sometime less) time to get the same fuel. So the ECM still only thinks it's injecting 140mm3 (100% load) but really we could be injecting a lot more fuel and thus added power.

PulseWidth_zpsa57c6404.jpg


Clear as mud??
 
^^^ Mud yeah that's what my brain is on this! Hey quick question: What timing are you guys running at 2000 rpm between 12 and 31 load? this is my cruise rpm at 65 and I drift around this load I've run as high as 9 and as low as 4 but best I CAN GET IS 20MPG AROUND 8! Wondering what others are running?
 
I would recommend somewhere between 6.5 and 8.5 depending on your fueling... 20mpg is quite good for a CR..

2005 - HE351/A5K - ARP - Arson lll - 70HP Nozzles
 
clear as crystal, "2000us pulse width gets you about 110mm3 of fuel at 14.5K psi, and 140mm4 at 23.2K psi. " that's a lot of psi to get to the 4th dimension, I know simple typo in an otherwise perfect post.

any consideration at all to the pilot shots contribution to the amount of fuel injected? or is it a paltry amount, or simply turned off in this stage of the game.

cruise at 65? yikes you'll get run over going that slow in NJ....... Add 10 and you're better off. 75 cruise here, about 2100 rpm timing about 8 at 12%, drops to about 6 in the 25 to 31% table, not sure on mpg but id about kill for 20. Just running a fresh tank with new tune, winter blend with too much around town to net much, but will see.
 
Pressure is magical :-)

The pilot, on the S06 and Jr, is still there and optional on the SSR. The largest pilot shot is 14mm3, so not a huge player but enough to make it quieter and a quicker ignition of the main.

I run about 7.5-8° at 15.5K to 16.5K.
 
Well glad to see I'm in the right range!
Mikmaze: cruise at 65? yikes you'll get run over going that slow in NJ....... Add 10 and you're better off. 75 cruise here, about 2100 rpm timing about 8 at 12%, drops to about 6 in the 25 to 31% table, why the drop I would think the higher the rpm the higher the degree can someone clarify this?!
Maybe that's why I'm messing up the timing?
 
So as load increases timing should drop? untill about 50% load then shoot back up? Doesn't make sense to me if you cruise at 8 at 2000 rpm then start up a hill load increases to 31 still at 2000 rpm timing will drop?? and stay there till you increase rpm? i set my cruise at 65 70 2000rpm +- 100 when not in a hurry to test MPG and this is a gray area I hope someone can clarify!
 
It's more of a plateau until 31.4 then drops and starts climbing as fueling increases, but I don't want all that fuel BTDC at I get above 30% so I back it off a little. In the 31.4 load cell I only run 70% of my fuel BTDC, where at 18.9 I run 100% of it BTDC and it's all injected 2.7° BTDC.
 
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